1. Field of the Invention
This field is generally related to management of cookies in a web browser.
2. Related Art
A cookie, also known as a web cookie, browser cookie, and HTTP cookie, is a piece of text stored on the computer of a user by a web browser. A cookie can be used for authentication, storing site preferences, shopping cart contents, or any other goal that can be accomplished through storing text data.
A cookie is comprised of one or more name-value pairs containing textual information, which may be encrypted for information privacy and data security purposes. The cookie is sent as a field in the header of the HTTP response by a web server to a web browser and then sent back by the browser each time it accesses that server.
Cookies may be set by the server with or without an expiration date. Cookies without an expiration date exist until the browser terminates, while cookies with an expiration date may be stored by the browser until the expiration date passes. Users may also manually delete cookies in order to save space or to address privacy issues.
As text, cookies are not executable. Because they are not executed, they cannot replicate themselves and are not viruses. However, since cookies may store private information and can be read remotely, they can be a privacy concern. Cookies can empower a server by facilitating online data collection and personalized advertising.
Most modem browsers allow users to decide whether to accept cookies, and the time frame to keep them. However, rejecting cookies makes some websites unusable.
Cookies may be divided into two kinds, session cookies and persistent cookies. A session cookie only lasts for the duration of a session that accesses a website. It will expire if a user closes his or her browser, or if a user has not visited the server for a certain period of time (called session idle timeout, in which case, the server will expire, invalidating the user session).
By contrast, a persistent cookie will outlast user sessions. If a persistent cookie has its Max-Age set to 1 year, then, within the year, the initial value set in that cookie would be sent back to a server every time the user visits the server. This could be used to record a vital piece of information such as how the user initially came to that website.
Persistent cookies can be used by advertising websites to keep track of information about users of the websites, allowing advertising websites to target online advertisements to users. While using persistent cookies in this way is quite helpful to owners of advertising websites, such a use of persistent cookies can provide advertisers with information that users would prefer that they not collect.
Thus, it would help users to offer a way to prevent persistent cookies from being used on their system, especially persistent cookies that are used for advertising purposes. Prior approaches have used preexisting lists of sites to manage opting out of cookies. For example, prior approaches have developed solutions for using opt-out cookies from preexisting lists to manage persistent cookies. However, there has not yet been a successful solution that has a mechanism in place to ensure that the opt-out cookies specified on that list are set all at once. Additionally, approaches have not provided that the opt-out cookies will persist across otherwise destructive user actions, such as a user clearing his or her browser cookies.